Hardt



e oit? ior erenk Sha-fte,

MCHXGAN, ASSGNOR T CON'INENTAL MOTORS 1910131', 01? DETROT, MICHIGAN, A CORPORATN OF VIRGINIA.

CRANILSHAFT.

@marinai .application filed.

Specification of Letters Patent.

Patented May t, 1919.

September 20, 191.6, Serial No. 121,099. Divided and this epplication filed June 8,

191B. Serial No. 239,650)

To all '1i-hom 'it may Com-em.'

it known that l, lionel-:ir A.. ll'mx Manor, a citizen of the United .States of America, residing,r at Detroit, in the count)v llayne and State ot lifliehiglan, have in rented Certain new and useful lmprorements in Crank-fliaits, of which the following ie Sieiilieation, reference heine; had to the neeonipanying drawings.

YlhiS ie a division of my other application led Septen'iher 20, 1916, ierial No. 121,998.

lfhie invention relates to bnlaneed crank ehotte 'l'or high Speed explosive engines and more partieula'rly to an arrangement of eonnterhelance `.for one of a Six throw, four hearing' type whereby three balance weights ere eo designed and disposed es to effectively neutralize the Couple eet up hy the revolution et the crank arms or eheelis and assoeiated erank pins end thereby n'iinimize the AHtrain that' otherwise put upon the hearing. 'one 'feature of the arrangement.- is the,

4dipoeition of' the weights or eounterhalance so that eaeh section ie independently taken care of hy e, companion weight.

The invention consists in the matters hereinafter Set forth, and more partieularly pointed out in the appended claims.

the drawings,

Figure 1 is a. 'View in elevation of a crank it embodying features ot the invention; l1igij. 2 ie a eet-tion taken on or about line n is a 'View in Section taken on or iine 111-!111 of Fig. 1; i. ie a View in Section taken on or .tine lfd-1V of Fig. 1; is View in Section taken on or ine lil-JV' of Fig. 1; and

u. diagram showing the disposi tion el? the ioreen diagraminatically.

" -jerring to the drawings, ar erank shaft 1' he eoneidered as divided into sections hearings or Qiournals. As herein 1, e erenk shaft hns a eeetion [i lying i an end' ienrnnl 1 and an interionrnal 2, with oppositely disposed are interconnected Iby a long or erani. erin and are suitably seo to the iournale hy crank arms or i' enel 7 oppoeitely and synnnetrieally .i3 @eed to each othera Referring4 to l? 1g.

iss

medi n @rentre 3 which 9, "the resultant et the centrifugalforce exe erted hy the arm G is elearl)v represented hy the line QS und that ol the, reversely disposed cheek 7 hy the linetl'l while the, resultant o'l these couples or iorees OS and UT and also ot the elongated cheelc 5, which is off-side and noty symmetrical to the center O, is likewise in the line 0l?. which ma)v lie coincident and substantially is coincident to the resultant of the lines OS and 0T. ceordingly a weight or halance S is applied to the crest of the cheek in such manner that itsinnss when revolving produces a centrifugal couple in the direction of the line @V which is directly opposed to and equal to the line ()l Consequently this portion of the shaft or the seetion thereof, is in running or dynamic balance.

An intermediate hearing or journal 10 with the short cheek 11. doulile crank pin 12. short crank arm or eheeh 12) and the 'journal 2 `forms the middle section B oi the shait. Both the short cheeks 13 und 11 are in the saine plane and conse p1entl \v their motion together with that olf the double crank pin 12 results in a moment or couple that may he represented hy the lines ORT. suitahle counterhalnnce 14 symmetrically disposed hetween the arms 11 and 13 on the middle, portion of the crank pin.12, is arranged to produce a couple OVI that is direetlyv opposite to and the equal ot' the couple @R1 so that the section B of the :shaft is in proper running` balance and there is no side thrust upon the bearings.

The Section C at the other end oi' the shaft is similar to section A with reverse position of elements. There is an outlet crank shaft liournal 15 Connected by a short cluiek 1G with a crank pin 17 and a rererselv disposed short cheek 18 connecting the 'journal 10 with a crank pin 19` a long cheek 20 coupling the pins 17 and 19. As seen in Fig. t, the resultant of one haltl ot the crank pin and the eheek 12 when in motion may he, repre sented by the lines OSL.. IThe resultant'y oi the cheek 16 and the crank pin 17 is properly indicated hy the line 0T2. rlhe revolution of the large cheek 20 causes a centrifugal couple. Uli, which is substantially eoineident also with the resultant ol' the couples 0S., and 0T2. Consequently a weight placed.

couple OV2 which counterbalances and eliminates the couple OR2 or the resultant of the couples OT2 and OS2. This brings the sectioninto complete balance.

As indicated in the diagram in Fig. 6 the couple OR on one side of the shaft is balanced'in section A so as to be nullified, as indicated'by the opposed. arrow heads. On the middle section B the resultant OR is similarly/4 counterbala'nced and eliminated and in section C thesame result is obtained in regard to the resultant ORT As a result of this construction a vcrank shaft is obtained that is capable of running at high speed in perfect balance. Each section is taken care of between the bearings so that there is no tendency of any sections to turn on any axis but that to which the shaft is necessarily confined by the bearings. vAs a consequence the wear on the bearings is reduced to a minimum and the strain and breakage due to crystallization from weaving or rapid vibration c is eliminated.

Obviously, changes in the details of c on struction may be made without departing from the spirit of my invention and I do not care to limit myself to any particular form or arrangement of parts.

lfVhat I claim is: 1. A crank shaft having four bearings 'and six throws, the section between the center bearings having correspondingly disposed crank arm cheeks and a counterbalance formed on the crank pin intermediate said cheeks adapted to balance the centrifugal couple set up thereby, the sections adjacent the end bearings each having a pair of oppositely disposed crank arm cheeks and 'an intermediate cheek, the ends of the latter being connected to the ends of the former by crank pins and a counterbalance formed 4on each intermediate crank arm cheek t adapted to balance the centrifugal couples set up by the companion'crank arms, cheek and pins. I

2. A six throw, four bearing crank shaft and arranged to produce a centrifugal ceu ple that is equal to and the opposite of the resultant of the centrifugal couples set up by the revolving short and long arm cheeks and pins, and also a counterbalance for the central section adapted to set up a couple that is the opposite of and the equal to the resultant of the centrifugall couples set up by the revolution of the crank arm cheeks and connecting crank pin of said sectiom` 3. A six throw, four bearing crank shaft having betweenv the end bearings and the adjacent intermedrate bearings, pairs of oppo sitely disposed short crankiarm cheeks and pairs of crank p ins projecting therefrom connected by long arm cheeks, a pair of short crank arm crank pin for two cranks intermediate the inner pair of journals, a counterbalance for I each end section disposed on the crest of the arranged to produce a long arm cheek and centrifugal couple -that is equal to and the opposite of the resultant` of the centrifugal couples sct up by the 'unbalanced masses of said section, and also a counterbalance for the central section adapted to set up a centrifugal couple equal and opposite to the resultant of the centrifugal couples set upvby the unbalanced masses of saidvcentral section.

In testimony whereof I affix my signature in the presence of two witnesses.

ROBERT A. W'EINHARDT. WVitnesses:

MARIE T. BARTHEL, Orro F. BARTHEL.

cheeks connecting a single 

